So just did a little more reading and realized we're a LOT more survivable in melee than I originally thought.
Kelly has Mesh Vest (Armour 4), and Toughness 4. If these are normal weapons then they'd be Primitive, would double the worn armour to 8 for chest, so she would take 12 less damage from any attack to the chest. (Specifically why I spent money on Mono.) but only 4 from non-chest areas.
McClane has full flak armour, so 4 armour all over, plus toughness 4 means 8 armour normally, 12 vs primitive.